Cook the farro according to the package directions (be sure to check to see if it needs an overnight soak!).

While the farro is cooking, combine the lemon juice, oil, lemon zest, garlic, and oregano in a glass measuring cup and whisk to combine.

When the farro is done (i like it al dente, retaining some chew but no crunchiness), drain the farro, put the cannellini beans in the pot you used to cook the farro, then dump the warm farro back in the pot on top of the beans. leave the farro and beans for a few minutes so the residual heat from the farro can warm the beans slightly. (if your beans started off colder than room temperature, you’ll need to heat them up slightly on their own as there won’t be enough heat from the farro.)

After the farro and beans have sat for a few minutes, add the arugula on top then pour the dressing over the top. stir to combine and distribute the dressing. add the tuna, red onion, radish, and tomatoes. stir again to mix everything together. add the feta and basil, stir gently one more time to distribute the cheese and basil without mushing up the cheese.

Serve the salad as is (slightly warm), at room temperature, or chilled. i ate the first serving as is after i made it then ate subsequent leftovers straight out of the fridge and liked it both ways.